Just a quick tip in case you didn't know, you can turn by setting bank/cyclic left/right to mouse left/right, and leave the "turn" keybinds blank. Then tilt the helicopter forward or raise the plane upward while banking, which will result in a turn while giving you the added ability of moving left or right without going forward/backward.

Sorry but that doesn't work. I just tried it out.

I use it all the time, I'll show you exactly what to bind.

Helicopter movement (in this order):

mouse up
mouse down
mouse left
mouse right
w
a
s
d

(the rest blank unless you want to bind, say, auto hover)

Plane Movement:

mouse up
mouse down
mouse left
mouse right
blank
w
a
s
d

(the rest blank unless you want to bind gear/flaps retraction)

You do not understand what I am saying.

On Plane Movement and on Helicopter Movement the options there get saved for both. For example if you bind Bank Left to something on Plane Movement it will get saved on Helicopter Movement. This causes problems.

I'm not saying it's not an issue, that's why I voted it up. I'm simply showing you how to avoid that issue, hence why I said "Just a quick tip" and not "I know how to solve this".